This section provides background information to facilitate a better understanding of the various aspects of the disclosure. It should be understood that the statements in this section of this document are to be read in this light, and not as admissions of prior art.
Conveyor belts are commonly utilized in a wide variety of commercial applications for the purpose of transporting products and materials. Such conveyor belts can serve in applications which have minimal demands, moderate demands, or in applications which are extremely demanding and which require heavy-duty conveyor belts for carrying heavy loads under adverse conditions, such as exposure to high temperatures. Conveyor belts can also very greatly in size and length. For instance, the conveyor belts used in mining applications can be very wide, for example over three meters wide, and very long, in some cases, on the order of many kilometers. They can also be up to about 7 centimeters thick or even thicker. In any case, heavy-duty conveyor belts are widely used for moving minerals, coal, cement, hot metal products, and a wide variety of manufactured products from one point to another. For instance, heavy-duty conveyor belts are often used in typical mining applications to transport minerals below the ground, to above the surface, and ultimately above ground to a desired location for processing and/or ultimately for transportation on rail road cars, trucks, barges, or ships. Heavy duty conveyor belts are also commonly used for moving hot cement from one location to another in cement plants and for transporting hot iron ore and metal alloys from blast furnaces. These are extremely demanding applications due to the heavy loads and extremely hot temperatures that are typically encountered.
Conventional conveyor belts which are used heavy duty applications where high temperatures can be encountered are typically comprised of a cured rubber as a top layer (the carry cover layer), a cured rubber as a bottom layer (the pulley cover layer), and a reinforcement layer which is situated between the top layer and the bottom layer. The prominent material used in such conveyor belts generally is a moderately flexible elastomeric or rubber-like material, such as an ethylene-propylene-diene monomer rubber (EPDM), and the belt is typically reinforced by a plurality of longitudinally extending steel cables or cords which are positioned within the belt and extend along the length thereof.
All conveyor belts are, of course, susceptible to normal wear and tear as well as damage from the material being transported and/or harsh environmental conditions. Over the years, substantial improvements have been made in the wear resistance of the rubber used as the cover carry layer of the conveyor belts and the useful service life of conveyor belts has been extended. However, conveyor belts which are routinely exposed to high temperatures generally have a shortened service life. Accordingly, there is a long felt need for a heavy duty conveyor which can be repeatedly or even continuously exposed to high temperatures while providing a longer service life without compromising the strength or reliability of the belt. Accomplishing these objectives has proven to be elusive and there continues to be a need for such a high temperature resistant conveyor belt which can withstand temperatures of greater than 200 deg C., or even 250 deg C. The need for such a high temperature resistant conveyor belt which can be manufactured in a commercially viable and cost effective manner remains today.